1) Field of the Invention
The present invention relates to a technology for simulating a topological change of a product caused by a micro-machining process with a high precision.
2) Description of the Related Art
In recent years, along with developments in machining techniques, miniaturization of semiconductor memories and MR heads has progressed greatly, and under this circumstance, the investment cost for forming the manufacturing processes of these products is increasing. Upon forming the manufacturing processes of these finely-machined products, it is very important to preliminarily simulate a topological change of a product after the machining processes so as to solve possible problems beforehand.
With respect to the invention used for simulating a topological change due to a micro-machining process, Japanese Patent Application Laid-Open No. 10-326756 has proposed a topology simulation system which can carry out high-speed simulation computing processes on an etched topology with high precision by using a Monte Carlo method.
Moreover, Japanese Patent application Laid-Open No. 63-1034 has proposed a method in which precision of a dry-etched topology simulation is improved by taking the incident direction of etching particles into consideration.
Furthermore, Japanese Patent Application Laid-Open No. 2000-269105 has proposed a process simulation system and a process simulation method in which a physical model, which indicates a physical phenomenon on an interface, is changed in response to properties of the interface with silicon so that simulation precision is improved.
However, along with the developments in micro-machining techniques, simulating processes by these systems and methods have come to fail to provide sufficient precision. The reason for this is because phenomena caused by shading effects and re-deposition effects and a difference in machined topologies depending on positions on a wafer, which can be ignored in conventional devices, have become influential to quality of a product due to advanced miniaturization in semiconductor memories and the like.
Moreover, with respect to the shading effect and re-deposition effect, the conventional two-dimensional simulation has failed to deal with these effects, and a three-dimensional simulation process is required; however, the three-dimensional simulation process requires a large amount of calculations, resulting in a problem of an increased processing time.